Cornell/UCB/UMich:
If money is a factor, go to in-state school (UCB, UMich), they are more than good enough.
If money is not a factor, for girl - go for Cornell - no matter what, you are in ivy circle.
for boy, either Cornell or UCB. Cornell has pretty much everything UMich has (barring good sports). Easy choice between those two. Cornell vs UCB depends on personal choices
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Caltech vs Y:
Hardcore science, natural sciences, academic career (going for Ph.D later) or STEM/engineering leadership, like to stay in west coast, more intimate faculty relationship - go for Caltech
(For girls - It's probably easier for a Chinese girl to find an Asian boy friend at Caltech)
Caltech coursework is managable. (It's not as hard as it seems for the students willing to put in work).
Aiming for wall street, consulting jobs, or product manager roles at tech companies, or go for law or medicine, like to stay in east coast, go for Yale.
Academic rep, Caltech = Y in US with international academic rep Caltech marginally better than Y.
But they are very different schools.